During the production of crude oil and gas, deposits can be laid down onto the surface of the pipes through which the crude oil, gas, water or a combination thereof is transported. These deposits may be organic (paraffin, asphaltenic), inorganic (scales such as calcium carbonate, barium sulfate, iron sulfide etc.), mineral (sand, clay etc.) or microbial (bacterial material) in nature. The deposits can accumulate on the surface of the pipe and provide a physical barrier that prevents corrosion inhibitor chemicals from penetrating and protecting the surface of the metal. Additionally, concentration cells can be set up between areas of the pipe that are covered with debris and those that are exposed. This can lead to high localized corrosion rates. Additionally the deposits can provide a safe haven for bacteria to grow. Biocidal chemicals can be ineffective at penetrating these deposits. The metabolic by-products of these bacteria can be very acidic and cause localized corrosion.
In the industry today there are few effective methods for measuring the accumulation of deposits on a pipe surface or the effectiveness of chemical programs for removing these solids. Pipeline inspection methods such as ultrasound and radiography can give a qualitative indication of the amount of debris in a pipe. These techniques are time consuming, expensive and require specialized equipment and trained personnel to perform the measurements.